The warning was directed towards "shops, food outlets, garages and all commercial premises" who serve the PSNI.

The statement also read: "We have been monitoring the situation of all these premises over the last number of months. They have 12 hours to desist. Do not come under our radar again."

Ulster Unionist Party MLA and Policing Board member Ross Hussey condemned the attempt to intimidate businesses as the work of "cowards and bully boys".

"They are so stuck in the past that they have no new ideas or tactics other than to attempt to carry forward a campaign that caused 30 years of misery and destruction and still did not break the link between Northern Ireland and the rest of the UK," he said.

"These threats are disgraceful and those responsible must be faced down and brought to book. This society has made its choice. It wants a police service and it wants normal policing.

"Those who would seek to threaten businesses who serve members of the PSNI are nothing more than bully boys and fascists with nothing to offer."

The threat has also been condemned as a throwback to the past by the Police Federation for Northern Ireland.

In a statement, a federation spokesperson said: "Officers are every bit a part of the community as are the local businesses on the receiving end of these threats.

"This won't prevent officers from doing their work on behalf of the entire community. Those behind the threats are a throwback to an era that thankfully is long since past."

Derry City and Strabane District Policing Command confirmed to the Belfast Telegraph that they have not received any complaints from businesses.